Evaluation of the intra-arterial wall surface is necessary for control of surgical procedures envisioned using laser ablation of tissue. Angioscopy inside vessels produces clear observation of the target sites provided adequate irrigation of saline solution is maintained. Precise quantitative location of the target is difficult. In addition, size constraints may limit angioscopy's usefulness in the coronary vessels. Preliminary fluorescent observation of human atheromatic and normal aorta specimens was performed using a fluorescence microscope with 450-490nm excitation. Fluorescence spectra collected using a multi-channel analyzer indicated clear intensity differences between the normal and atheromatic tissue. These differences were reduced an eliminated by ablation of the atheroma by either an argon laser (514nm) or a xenon chloride (308) excimer laser.